Prosecutors are facing a major hitch in their case against two former tech company executives accused of paying bribes in India: They can’t get their star witness into the country.

The long-awaited trial of ex-Cognizant President Gordon Coburn and ex-chief legal officer Steven Schwartz over allegations that they bribed Indian officials $3.6 million to expedite the construction of an office building was scheduled to begin Monday in federal court for the District of New Jersey. But a key witness, former Cognizant vice president of administration Srimanikadan Ramamoorthy, is currently under investigation by Indian authorities over his role in the bribery scheme and had surrendered his passport.